<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>用户输入信息</title>
</head>

<body>
    <script>
        // 用户输入本月的日期（即1日-31日）
        let number = parseInt(prompt("请输入星期数"));
        number = number % 7;
        switch (number) {
            case 1:
                alert("今天星期一");
                break;
            case 2:
                alert("今天星期二");
                break;
            case 3:
                alert("今天星期三");
                break;
            case 4:
                alert("今天星期四");
                break;
            case 5:
                alert("今天星期五");
                break;
            case 6:
                alert("今天星期六");
                break;
            case 0:
                alert("今天星期日");
                break;

        }
    </script>
</body>

</html>